In order to monitor and analyze aircraft condition, a large number of sensors are mounted on the aircraft. Those sensors are used to detect and collect massive data of aircraft condition such as acceleration, air speed, altitude, airfoils configurations, external temperature, cabin temperature and pressure, engine performance and so on. Those data of aircraft condition play a very important role in flight safety.
When an aircraft malfunctions, data of aircraft condition reflecting operating status of an aircraft will be abnormal. Various reasons contribute to the malfunction of an aircraft. Therefore, sometimes it is difficult to locate malfunction of an aircraft. Specifically, malfunction might occur to component of aircraft itself, to sensors, and also to signal transmission device for transmitting data of aircraft condition measured by sensors.
On the other hand, malfunction also might occur to control system of an aircraft. Control system of an aircraft receives control command, converts the control command into control signals and transmits the control signals to components of the aircraft, and then components of the aircraft perform corresponding actions. It is also difficult to locate malfunction of operating system of an aircraft. Specifically, malfunction might occur to moving parts of an aircraft, to control command input device, and also to control signal transmitting device. In certain cases, malfunction also might occur to DFDAU (Digital Flight Data Acquisition Unit).
As far as the location of malfunctions of an aircraft is concerned, the location of malfunction may be accelerated if the possibility that malfunction might occur to a signal transmission device or DFDAU can be eliminated. In prior art, there is no such instrument specifically for testing a signal transmission device or DFDAU. In many cases, it is required to disassemble an aircraft so as to complete the test of a signal transmission device. Besides, since the type of measuring signals and control signals in an aircraft is very complicated, the test of a signal transmission device of an aircraft also becomes complicated and difficult. Therefore, there is a need in the art a test apparatus and method specific to signal transmission device or DFDAU of an aircraft.